$ {-7\cdot \left[ \begin{array}{cc} 1 & 2 & -2 \\ 3 & 0 & -1 \end{array} \right]=}$
Solution: The Strategy To multiply a matrix by a scalar, we multiply each term of the matrix by the scalar. Multiplying each term $ {\begin{aligned}-7\cdot \left[\begin{array}{rr} {1} & {2} & {-2} \\ {3} & {0} & {-1} \end{array}\right]&=\left[\begin{array}{rr} -7\cdot{1} & -7\cdot{2} & -7\cdot{-2} \\ -7\cdot{3} & -7\cdot{0} & -7\cdot{-1} \end{array}\right] \\\\&=\left[\begin{array}{rr} {-7} & {-14} & {14} \\ {-21} & {0} & {7} \end{array}\right]\end{aligned}}$ Summary $ {-7\cdot \left[ \begin{array}{cc} 1 & 2 & -2 \\ 3 & 0 & -1 \end{array} \right]=\left[ \begin{array}{cc} -7 & -14 & 14\\ -21 & 0 & 7 \end{array} \right]}$